Positive drive control for endless band printers



H. P. KECK 3,164,086

Jan. 5, 1965 POSITIVE DRIVE CONTROL FOR ENDLESS BAND PRINTERS 2 Sheets-Sheet 1 .Filed July 50, 1962 l EN EMEI'.

: Il EI'H, '1, 5 1; I

. Mew.- WaZJP/ieck H. P. KECK Jan. 5, 1965 POSITIVE; DRIVE CONTROL FOR ENDLESS BAND PRINTERS 2 Sheets-Sheet 2 Filed July 50, 1962 waafijieck United States Patent 3,154,036 POSITIVE DRIVE CUNTRGL FUR ENDLESS BAND PRINTERS Harold P. Keck, 421) Charlotte St, Crystal Lake, 111.,

assignor of one-third to Jack W. Robbins and one-third to Bernard Robbins, both of Chicago, Ill.

Filed Juiy 30, 1962, Ser. No. 213,327 6 Claims. (Cl. 101-111) stamp of the foregoing character wherein the type or printing band may be moved or rotated to selective position without the persons fingers engaging the surface of said band.

It is well known in connection with conventional hand stamps that the type or printing bands are rotated by means of wheels or discs which have knurled surfaces. In such constructions the band in the initial instance must be unusuflly taut, that is, the band is tensioned to prevent slippage. In the initial use of such a device, by virtue of the tension of the band with respect to the surface of the wheel, it is hard to move or rotate the band. However, as the band loosens or slackens with usage it becomes objectionable as it tends to creep with respect to the knurled disc. Thus, there is no positive control between the type band and the means for rotating same. With the present invention, the printing band need not be taut as in the case of the prior structures since it is under a'positive control by means of the gear teeth in engagement with the inwardly extending teeth on the printing band.

In conventional printing units in which the type band rotates over a stationary bridge at the printing end, the printing ink will in usage adhere under the type band and to the bridge and cause the type band to stick to the stationary bridge, which is decidedly objectionable. With this invention the type band rotates with a rotatable member at the printing end of the printing unit and the sticking of the type band and the objections attendant thereto are eliminated.

Another object of this invention is to provide a hand stamp whereby with each actuation of the selector means the type band is rotated to aline the type in printing position. In prior art constructions the type is not always alined and it requires additional manipulation or rotation of the type band to effect alinement.

Other objects and advantages will become apparent as this description progresses.

In the drawings:

FIGURE 1 is a front elevational view showing the embodiments of this invention incorporated in a hand stamp.

FIGURE 2 is a sectional view taken on lines 2-2 of FIGURE 1.

FIGURE 3 is an enlarged exploded view in perspective of the type band, the upper gear and indexing member, the selector member, and the lower gear.

FIGURE 4 is a view of the hand stamp partly in section taken on lines 4-4 of FIGURE 1, but with the hand stamp depressed and in printing position.

FIGURE 5 is a view taken on lines 5-5 of FIGURE 1, and

FIGURE 6 is a sectional view taken on lines 66 of FIGURE 1.

3,ib i,85 Patented Jan. 5, 1965 The hand stamp includes a main base frame generally indicated at 10 .and a depressible sub-frame generally indicated at 12. The depressible sub-frame 12 carries the printing unit generally indicated at 14. The main base frame has a pair of side members 16 connected by a top cross member 18. Extending upwardly of the top cross member 18 is a tubular member 19 within which is slid- .ably supported a stem 20, the bottom of which is secured to the depressible sub-frame 12. The upper portion of the tubular member 19 and the stem 20 is not shown, however, it is of conventional design and it is intended that the stem be connected to a conventional spring loaded handle to be manually depressed, to thereby depress the depressible sub-frame 12 for the purpose of moving the printing unit to printing position, as best shown in FIG- URE 4.

The bottom of the main base frame may be integrally formed with the side members 16, and said bottom comprises a pair of spaced cross bars 22 providing an enlarged intermediate rectangular shaped opening 24 to accommo date the printing unit on the downstroke. Rubber gaskets 25 are secured to the underside of the cross members of the base. The side members 12 of the main base frame 1% are shaped to provide at their lower ends vertically extending channels 26 to accommodate the lugs or ears on the depressible sub-frame 12.

The depressible sub-frame 12 has a pair of spaced sides 28 joined by a top cross member 2h, the top cross member being secured to the stem 20 connected to the handle heretofore mentioned. The sides of the depressible subframe have widened portions 30 at the top and widened portions 31 at the bottom with a vertically extending section 32 of reduced width therebetween (FIGURE 5).

Secured to the top widened portions 30 of the side walls are flat spring clips 34 which extend below the top widened portions 3th and into the open space of the depressible frame for engagement with the printing unit 14. The widened bottom portions31 of the sides of the depressible frame has an arcuate surface 33 to receive the sides of the printing unit, to be described. The sides of the depressible sub-frame 12 have outwardly extending lugs 35 which ride in the vertical channels 26 of the main frame 10.

The printing unit 14 is adapted to be detachably secured to the depressible sub-frame. The main base frame 14? is provided with a pair of rearwardly extending ears 36. The ink pad unit comprises a rectangular shaped holder 41 provided with rearwardly and upwardly extending extensions 42 which are pivotally secured by a pin 38 to the ears 35 on the main base frame It). The ink pad holder is adapted to support a conventional ink pad 44 in the usual manner.

In its non-printing position, the printing unit 14 is in its elevated position, as shown in FIGURES I and 2, and in this position the ink pad unit 44 is in a horizontal position, with the ink pad in engagement with the type bands of the printing unit for inking the type on said type hands. When the hand stamp is operated by depressing the handle, the depressible sub-frame 12 is moved downwardly, as shown in FIGURE 4, and with said downward movement the ink pad unit 41) is moved to the position shown in FIGURE 4, away from the printing unit 14, to allow the printing unit to move into printing position, as shown in said figure.

A spring 46 is coiled around the pivotal pin 38, with the opposite ends of the spring engaging the extension 42 of the ink pad unit and the ear 36 of the main frame to normally urge the ink pad unit to the position shown in FIGURES 1 and 2. Thus, when the handle is released, the spring 46 will cause the ink pad unit to be moved upwardly to the horizontal position as the spring loaded oneness V 3 handle returns the depressible subfrarne 12 to its uppermost or raised position. The foregoing features are generally conventional in the art and no invention is claimed therein.

The features of this invention reside in the specific details of the printing unit which includes the type bands, the gearing arrangements and their geared connections with the type bands, and the selector means for operating same.

The printing unit which forms the subject matter of this invention is generally indicated at M and includes a frame generally indicated at 50 having a pair of spaced side mem bers 52 connected across their upper ends by a cross shaft 54- and at their lower ends by a cross shaft 56. There is also an intermediate cross shaft as. The top, bottom, and intermediate cross shafts are fixedly secured to the side members of the printing unit. The side members 52 each have spaced flanges 53 to provide channel shaped side members which are engaged at their upper ends by the spring clips 34 and at their lower flared ends by the arcuate surface 33.

Rotatably mounted on the upper cross shaft 54 as a unit is a gear and indexing disc generally indicated at 6% and best shown in perspective in FIGURE 3. The gear 62 is formed of nylon and has teeth 63. The indexing disc 66 is secured to the gear 62 to rotate therewith. The indexing disc has ratchet type teeth 67.

Rotatably mounted on the intermediate cross shaft 58 V is an intermediate gear 68, and rotatably mounted on the lower cross shaft 56 is a gear "it? formed of nylon. The intermediate gear is in engagement with gears 62 and 7t Rotation of the upper gear 62 in one direction will rotate the intermediate gear 68 in the opposite direction to rotate the lower gear '70 in the same direction as the upper gear 62. The lower gear 7d, best shown in FIGURES 3 and 4, has inwardly and radially extending ribs '71 adapted to engage the cross shaft 56. The ribs '71 permit the lower gear to rotate freely when rotated in one direction, but tend to resist rotation of the gear in the opposite direction, as will be subsequently explained.

The continuous type band generally indicated at '72 is best shown in FIGURES 3 and 4. The continuous type band is provided with inwardly extending teeth 74. The type band is adapted to be positioned on the upper and lower gears 62 and 70, as best shown in FIGURE 4, so that rotation of said upper gear olwill operate to rotate the intermediate gear 68, as well as the lower gear 70, and thereby positively rotate the type band. The three aforementioned gears are in vertical alinement and the type .band is always in positive engagement with the upper and lower gears. In the illustration shown there is a series of four type bands and likewise there are four sets of gears, just described, for operation of the type bands. The type band 72 is provided with the usual type or print indicia 76 thereon as is conventional.

The selector member for operating the type band is generally indicated by the numeral 78 and is best shown in FIGURE 3. The selector member is positioned and supported on the upper shaft 54 so that when actuated the pawl of this selector member will engage the indexing disc 66 to rotate the indexing disc as Well as the upper gear 62. The selector membercomprises a plate 80 having a central opening 81 whereby it is supported on the shaft 54. The plate 80 is positioned adjacent the indexing disc as but has a smaller circumference than that of the indexing disc.

Extending radially outwardly and forwardly of the plate 80 is a projecting finger or extension 82 which has a flange portion 84 at the front end to be manually engaged by a persons finger in operating the selector. Extending radially outwardly of the rear of the plate 80 is an extension 86 which terminates in a laterally extending inverted U-shaped section having spaced sides 87 and 88 joined by a flat cross-piece S9. The sides 87 and 855 under the crosspiece 89 are each provided with a slot $8. A pawl gen erally indicated at 92 is made of spring metal and has a T-shaped end 93 which fits within the slots 99. The pawl then extends forwardly underneath the cross-piece 3% and between the sides 87 and S8 and then is reversely bent and extends downwardly and inwardly as at 9?. for engagement with the ratchet teeth 6'7 of the indexing disc The pawl is always in engagement with the teeth 67 of the indexing disc and the pawl is normally urged outwardly so that the T-shaped end 93 of the pawl which is positioned in the slots in is sufiicient for securing the pawl to the sides 87 and $3 without the use of other fastening elements.

The upper gear 62 which is afiixed to the indexing disc 66 rotates therewith. Rotating the selector plate it clockwise, as viewed in FIGURE 4, that is, by manually engaging the finger 82 and moving it upwardly, will cause the plate 86 to rotate on shaft 54 and the pawl )2 will engage a ratchet tooth 67 to rotate the indexing disc 66 and with it rotate the upper gear 62 clockwise, simultaneously rotating the inter-mediate gear 68 counterclockwise and the lower gear 7%) clockwise and thereby rotating the printing or type band 72 clockwise. Rotating the actuating or selector member in the opposite direction, namely, counterclockwise, as viewed in FIGURE 4, as by engaging the finger 82 and moving it downwardly, will cause the spring pawl 98 to override the ratchet teeth 67 and impart no movement to the gears. The inwardly extending ribs 71 on gear 70 will not interfere with the free rotation of the lower gear it? in the clockwise direction, but will restrict rotation of said gear in the opposite or counterclockwise direction, thereby preventing the type band 72 from accidentally rotating on the return of the selector member.

The type band 72 and gears are so arranged that the movement of the selector finger or extension 82 from the position shown in FIGURE 2, namely, where the finger is substantially at right angles to the longitudinal axis of the unit, to the uppermost position, which is adjacent the upper end of the main frame, will describe an are just suflicient for the gears to rotate the type band one printing space. Thus, if the operator desires to rotate the type band he moves the finger 82 from the position shown in FIGURE 2 to that shown in FIGURE 4 to effect a rotation of the type hand one printing space. It then becomes relatively easy for an operator to move the type band to the desired print designation merely by moving the finger the number of times it is desired to rotate the type band to the particular print designation.

With the four type bands, as best seen in FIGURE 6, two selector members 78 are positioned to the left of center and two to the right of center. The type bands are rotated for setting when the depressible frame is depressed, as shown in FIGURE 4.

The intermediate gear 68 is important in that it drives or rotates the lower gear 70, thus, the two gears, namely, the upper and lower gears 62 and 7t are geared together to rotate the type band 72 under a positive controlled connection. The lower gear 79 forms, in eltect, a rotating bridge at the printing end for the type band.

The printing unit 14 is removably secured to the depressible sub-frame 12 and engagement is effected by inserting the printing unit so that the spring clip members 34 on the depressible sub-frame 12 engage within the upper part of the channeled side members 52 of the printing unit. The lower ends of said side members of the printing unit engage the arcuate surface 33 of the sides of the depressible sub-frame.

While I have shown the printing unit in combination with a depressible hand stamp in which the sub-frame and printing unit move vertically or reciprocate vertically, it will be understood that this invention has application to other types of hand stamps, such as where the printing unit rotates as it moves to printing position, or other types of printing units which are supported in stationary frames.

It will be understood that various changes and modi- 3 fications may be made from the foregoing without departing from the spirit and scope of the appended claims.

What is claimed is:

1. A printing unit for a hand stamp comprising a supporting frame, a first gear positioned adjacent one end of said frame, a second gear positioned adjacent the opposite end of said frame, and an intermediate gear in mesh with said first and second gears, a printing band having printing characters spaced therearound and having inwardiy extending teeth under tension and in positive driving engagement with said first and second gears and adapted to be driven by said gears, a ratchet member coaxial with one of said gears and rotatable with said gear, a movable member rotatably supported on the same axis as said ratchet member and engaging said ratchet memher and having means-extending radialiy outward therefrom so that manual rotation of said movable member will engage said ratchet member to rotate said gear when moved in one direction only in increments corresponding to character spaces on said band, said gear when rotated adapted to rotate said other gears in positive driving engagement and positively drive said printing band.

2. A structure defined in claim 1 wherein there are a plurality of sets of gears each comprising a first and second and intermediate gear, and wherein each set of gears supports and drives a separate printing band.

3. A structure defined in claim 1 wherein one of the gears is supported on a shaft and said gear is provided with internal ribs in cooperative engagement with said shaft to permit rotation in one direction and resist rotation in the opposite direction.

4. A structure defined in claim 3 wherein the internal ribs on said one gear are off center.

5. A structure defined in claim 1 wherein there are stop means to control the movement of the movabie member to permit rotation of the type band one printing space with each manipulation of the movable member.

6. A structure defined in claim 1 wherein the first and second gears are made of nylon.

References @ited in the file'of this patent UNITED STATES PATENTS 402,771 Scotford May 7, 1889 798,572 De Pew Aug. 29, 1905 1,503,566 Wallenstein Aug. 5, 1925 2,707,038 Szady Apr. 26, 1955 2,762,297 Baer Sept. 11, 1956 2,857,777 Porter Oct. 28, 1958 2,901,540 Canepa Aug. 25, 1959 2,950,048 Luhn Aug. 23, 1960 2,983,219 Weissrnan May 9, 1961 3,099,955 Keck May 21, 1963 FOREIGN PATENTS 147,312 Sweden Oct. 19, 1954 

1. A PRINTING UNIT FOR A HAND STAMP COMPRISING A SUPPORTING FRAME, A FIRST GEAR POSITIONED ADJACENT ONE END OF SAID FRAME, A SECOND GEAR POSITIONED ADJACENT THE OPPOSITE END OF SAID FRAME, AND AN INTERMEDIATE GEAR IN MESH WITH SAID FIRST AND SECOND GEARS, A PRINTING BAND HAVING PRINTING CHARACTERS SPACED THEREAROUND AND HAVING INWARDLY EXTENDING TEETH UNDER TENSION AND IN POSITIVE DRIVING ENGAGEMENT WITH SAID FIRST AND SECOND GEARS AND ADAPTED TO BE DRIVEN BY SAID GEARS, A RATCHET MEMBER COAXIAL WITH ONE OF SAID GEARS AND ROTATABLE WITH SAID GEAR, A MOVABLE MEMBER ROTATABLY SUPPORTED ON THE SAME AXIS AS SAID RATCHET MEMBER AND ENGAGING SAID RATCHET MEMBER AND HAVING MEANS EXTENDING RADIALLY OUTWARD THEREFROM SO THAT MANUAL ROTATION OF SAID MOVABLE MEMBER WILL ENGAGE SAID RATCHET MEMBER TO ROTATE SAID GEAR WHEN MOVED IN ONE DIRECTION ONLY IN INCREMENTS CORRESPONDING TO CHARACTER SPACES ON SAID BAND, SAID GEAR WHEN ROTATED ADAPTED TO ROTATE SAID OTHER GEARS IN POSITIVE DRIVING ENGAGEMENT AND POSITIVELY DRIVE SAID PRINTING BAND. 